Imaging interferometric microscopy–approaching the linear systems limits of optical resolution.

Abstract

The linear systems optical resolution limit is a dense grating pattern at a lambda/2 pitch or a critical dimension (resolution) of lambda/4. However, conventional microscopy provides a (Rayleigh) resolution of only ~ 0.6lambda/NA, approaching lambda/1.67 as NA ?lambda1. A synthetic aperture approach to reaching the lambda/4 linear-systems limit, extending previous developments in imaginginterferometric microscopy, is presented. Resolution of non-periodic 180-nm features using 633-nm illumination (lambda/3.52) and of a 170-nm grating (lambda/3.72) is demonstrated. These results are achieved with a 0.4-NA optical system and retain the working distance, field-of-view, and depth-of-field advantages of low-NA systems while approaching ultimate resolution limits.

Super resolution imaging using interferometric masking technique

“…Different super resolution techniques like grating based [1], fringe illumination [2,3] and interferometry based [4,5] have been mentioned in literature to achieve high resolution.…”

Nanophotonics for optical super resolution from an information theoretical perspective: a review

“…However, they do not provide significantly high synthetic aperture values. For this reason, other approaches [68][69][70][71][72] apply the same underlying principle but using medium NA lenses (ranging from 0.3 to 0.7). This fact permits the definition of synthetic numerical apertures higher than the theoretical value for air-immersed imaging system but with the added value of the unique feature provided by holography: the recovery of the complex amplitude distribution of the wavefront that is leaving the sample.…”

Joint approach of the sub-holograms in on-axis lensless Fourier phase-shifting synthetic aperture digital holography

“…To address this, on-axis lensless Fourier phase-shifting configuration has been found to be the best solution in the maximum satisfaction for both the recording condition and the separating condition in DH. Furthermore, enlarging the numerical aperture (NA) of DH recording system, for example, short distance configuration [5,6], synthetic aperture configuration [7][8][9][10][11][12][13][14][15][16][17][18]and microscopy configuration [19][20][21][22][23][24], has been proven to be the effective approach in improving the resolution of the reconstructed image. Specially, since no extra components are added and complex adjustments are needed, spatial synthetic aperture digital holography (SADH) in which multiple subholograms are recorded by moving the CCD detector transversely to different spatial positions and composed a larger synthetic aperture digital hologram [8][9][10][11], has been widely employed to enlarge the NA of DH.…”